and I found some problems
1. the last boss can be instant killed with bomb
and other small problems are
2. missiles are too good than other weapons medium damage but with its high accurate it becomes a high damage weapon.Compare with Meteor cannon it also has more advantages in general.
3.I regretted choosing plasma sprader in transition,low accurate,I rather to choose other near price of weapon.
4.even if my ship lv is maxed(4),sometimes in the end it also says my ship leveled up.
There's one certainly dead end are waiting you,even if you have all the skills and the best weapon,any bullet that you shoot can hits an enemy. The last weapon doesn't make area damage,and when the monster spawn rate faster than your killing rate,the remained time is your health.